1. Field of the Invention
The invention relates to a decorative stone made from glass with a facetted front, and a mirrored rear converging from the periphery of the stone to a point provided with an adhesive.
2. Description of Related Art
It has long been known (see GB 1 325 293) to provide glass decorative stones with an adhesive on the rear, so that they can be ironed individually or in the form of a pattern applied to transfer foils onto a textile substrate. In areas of application where ironing is inadvisable, for imitation tattoos in particular, a pressure-sensitive adhesive is used instead of the usual hot-melt adhesive.
Decorative stones coated with adhesives basically have a planar rear, and the corresponding stone shape is known commercially as a rose. In exceptional cases, stones with a concave rear have even been proposed in order to improve adhesion (see WO 97/41746 and DE 26 46 727).
There is a need to configure stones of the type described in the Background such that they can be attached to a substrate using an adhesive. In particular, this is the case when the stones have a planar central area (table) on the front and their type of cut (xe2x80x9cchatonxe2x80x9d) thus resembles a diamond.
In the case of diamonds, a chaton normally has an angle between 96xc2x0 and 98xc2x0 at the point of the stone. In spite of the substantially different refractive index, with a glass stone, an optical behavior comparable to diamonds of a similar size is obtained. This is possible because the total reflection occurring on the rear of diamonds is replaced by mirroring. The term mirroring, as used herein, means treating a surface of an object, such as with silvering, to create a more reflective surface.
Chatons with a standard angle have already been used occasionally on textile substrates, but these are limited to very small stones with a diameter of less than 2.5 mm, and particularly soft substrates, because the gap between the periphery of the stone and substrate is otherwise too large.
If required, a certain increase in the diameter of adhesive chatons would be obtainable if the flattest of the chatons previously proposed were to be used, as have been described with an angle of 130xc2x0, and claimed for with an angle of up to 150xc2x0 in AT 393 597. Larger stones have actually been used, however, configured with a flat rear, that is to say in rose form. In contrast to rivoli stones, when stones are chaton-cut, that is to say with a front table, this results in a central part that gives a less lively impression. Stones with a substantially increased brilliance are unexpectedly produced when the rear angle is made large enough for the adhesion of the stones no longer to be obstructed by the corresponding slight unevenness of the rear side of the stone.
The decorative stone made of glass of the present invention has a facetted front and a mirrored facetted rear converging from the periphery of the stone to a point, and the rear of the stone is provided with an adhesive. The decorative stone is provided with an angle of more than 150xc2x0 between opposing surfaces of the rear of the stone.
In another aspect of the present invention, the decorative stone is provided with an angle of more than 160xc2x0 between the two opposing surfaces of the rear of the stone.
In yet another aspect of the present invention, the decorative stone is provided with an angle between 170xc2x0 and 175xc2x0 between the two opposing surfaces of the rear of the stone.
Further, the front of the decorative stone of the present invention is provided in the central area of the stone with a planar surface, and the rear of the adhesive coated stone is planar.